Script Pushdown to Add New Site Columns to Existing Child Lists

We have created a Feature that modifies an existing Site Column definition to add a new site column. Unfortunately, we can’t use the new column in pre-existing page layouts and pages until after we have used the “Add from existing site columns” (which calls AddFieldFromTemplate.aspx) to push the new column down to the lists in the subsites.

Q: How can I script the action that AddFieldFromTemplate.aspx is taking so that when the Feature is updated via STSADM, all dependant subsites, lists, page layouts and pages are automatically updated